标签：装饰者模式   C#   

这个场景在RPG游戏中很常见. 下面我们使用装饰者模式去实现它.

一 :所有加成类的基类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DecoratorPatternDemo.com
{
    /// <summary>
    /// 所有加成战斗加成基类
    /// </summary>
    public abstract class BaseAddtition
    {
        /// <summary>
        /// 被装饰者
        /// </summary>
        private BaseAddtition _decor = null;
        /// <summary>
        /// 本加成的power
        /// </summary>
        protected Int32 _power = 0;
        /// <summary>
        /// 战斗力描述
        /// </summary>
        protected string _describe = string.Empty;
        /// <summary>
        /// </summary>
        /// <param name="describe">描述</param>
        /// <param name="power">战斗力</param>
        /// <param name="decor">被装饰者</param>
        public BaseAddtition( string @describe, Int32 @power = 0 , BaseAddtition @decor = null)
        {
            this._describe = @describe;
            this._power = @power;
            this._decor = @decor;
        }
        /// <summary>
        /// 统计战斗力
        /// </summary>
        /// <returns></returns>
        public Int32 StatisticsPower()
        {
            if (null != this._decor)
            {
                return this._decor.StatisticsPower() + this._power;
            }
            else
            {
                return this._power;
            }
        }
        /// <summary>
        /// 获取描述
        /// </summary>
        public abstract string Describe { get; }
    }
}

二 : 各种加成

①:战靴

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DecoratorPatternDemo.com.cn
{
    /// <summary>
    /// 战靴加成战斗力
    /// </summary>
    public sealed class BootsAddtition : BaseAddtition
    {
        public BootsAddtition(string describe, Int32 power, BaseAddtition decor) : base(describe, power, decor)
        {
        }

        public override string Describe
        {
            get { return string.Format(@"{0}{1}的战斗力:{2}", this._describe,"加成", this._power); }
        }
    }
}

②:护膝

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DecoratorPatternDemo.com.cn
{
    /// <summary>
    /// 护膝的加成战斗力
    /// </summary>
    public sealed class KneepadAddtition : BaseAddtition
    {
        public KneepadAddtition(string describe, Int32 power, BaseAddtition decor) : base(describe, power, decor)
        {

        }

        public override string Describe
        {
            get { return string.Format(@"{0}{1}的战斗力:{2}", this._describe,"加成", this._power); }
        }
    }
}

三 : 主角

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DecoratorPatternDemo.com.cn
{
    /// <summary>
    /// 主角的基本战斗力
    /// </summary>
    public sealed class LeadBasePower : BaseAddtition
    {
        public LeadBasePower(string describe, Int32 power) : base(describe , power, null )
        { }

        public override string Describe
        {
            get { return string.Format(@"{0}{1}的战斗力:{2}", this._describe , "基础", this._power); }
        }
    }
}

四 : 测试

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using DecoratorPatternDemo.com;
using DecoratorPatternDemo.com.cn;

namespace DecoratorPatternDemo
{
    class Program
    {
        static void Main(string[] args)
        {
            BaseAddtition @leader = new LeadBasePower(@"主角", 100000);
            Console.WriteLine(@leader.Describe);
            //用战靴来装饰主角
            BaseAddtition @boots = new BootsAddtition(@"战靴", 12, @leader);
            Console.WriteLine(@boots.Describe);
            //用护膝装饰战靴(间接装饰主角)
            BaseAddtition @kneepad = new KneepadAddtition(@"护膝", 200, @boots);
            Console.WriteLine(@kneepad.Describe);

            //计算综合战斗力
            Console.WriteLine(@"总战斗力 : {0}", @kneepad.StatisticsPower());
            Console.Read();
        }
    }
}

注意层层装饰 , 递归调用

五:结果

?????为何需要考虑装饰者模式 : 当加入新的装备后 ???? 可以直接继承BaseAddtition抽象类.实现了开闭原则.

装饰者模式

标签：装饰者模式   C#   

原文地址：http://blog.51cto.com/aonaufly/2093921